MusicaltechMusicaltech specialize in top digital audio concepts using powerful programmable logic devices. Original designs include total replacement of off-the-shelf chips - seen by the Musicaltech team as a limitation in performance and flexibility. Information about one of the the most sophisticated dacs avaialable for DIYers, either multibit or delta-sigma, are available in the dedicated forum.

- Are you generating the clock in the FPGA (soft PLL), or are you using crystal(s)?
- Is the Bytemorph DF oversampling to 768kHz or 384 kHz?
- Are you doing oversampling in integer multiples, or ASRC? I see only 384/768 kHz mentioned - for n x 44.1 kHz input I'd like to see 352.8 or 705.6 kHz.

There are 2 main clocks involved, and both are external XO's. One is a high-frequency clock involved in sampling the input signal; second - and key of the reclocking system, combined with fpga internal ram buffer - is the Si570 DCO. This allows the creation of a PLL entirely in the digital domain (all-digital-pll). The performance of the ADPLL is essentially given by the performance of the Si570, which offers a remarkably low phase noise for a DCO.
The Bytemorph DF is actually a collection of 3 independent filters; they are indeed integers (no ASRC). There is a 8x filter for 44.1k and 48k; a 4x filter for 88.2 or 96k input; and a 2x filter for 176 and 192k. The filters are switched on-the-fly when sample rate changes. I will come back with detailed DF performance in the next posts.

Hi Lupulroz
I'll be happy to receive it as soon as possible; I have a lot of HD Tracks at 24/192 kHz to listen. For the moment I can`t use my old DAC with CS4398 for 24/192kHz sample rates I play them from my Dune HD Max media player.

Maybe you will help me to take from this player via HDMI I2S signal for this DAC.

Look forward for more information and opinion about this DAC if someone already have it.

Impressive set of features, well done!
I notice that the graphs in posts 13, 14 have switched places.
Any room left for different types of digital filters...minimum phase apodizing and the likes? Accesible via remote of course

Hi Lupulroz
I'll be happy to receive it as soon as possible; I have a lot of HD Tracks at 24/192 kHz to listen. For the moment I can`t use my old DAC with CS4398 for 24/192kHz sample rates I play them from my Dune HD Max media player.

Maybe you will help me to take from this player via HDMI I2S signal for this DAC.

Look forward for more information and opinion about this DAC if someone already have it.

Hi Gabriel,
a HDMI receiver core is possible to implement in a future release of software. However this require lots of testing and there is also the problem of HDCP (digital content protection) which usually applies to HDMI.

Impressive set of features, well done!
I notice that the graphs in posts 13, 14 have switched places.
Any room left for different types of digital filters...minimum phase apodizing and the likes? Accesible via remote of course

Thank you Sidiy! You are right, I switched graphs, my bad
About different digital filters : that's the idea! There are enough hardware resources ,in short time a variety of filters will be available, via remote. We are working now on system to upgrade the firmware via usb input, to make the board easy upgradable in the field.